The spinosyns are a novel family of fermentation-derived natural products that exhibit potent insecticidal activities. Spinosad, a naturally-occurring mixture of spinosyn A and spinosyn D, is derived from a soil actinomycete bacterium species, Saccharopolyspora spinosa (Mertz and Yao 1990) and has successfully established its utility for crop protective applications in the agrochemical field in many countries including India. Recently, a new class of spinosyn was discovered from S. pogona NRRL 30141 (Hahn et al., 2006). The butenyl-spinosyns, also called pogonins, are very similar to spinosyns, differing in the length of the side chain at C-21 and in the variety of novel minor factors.
Fermentation development studies showed that for high spinosyn production, pH control and slow use of the carbon source was essential. Although, production of various insecticides by culturing different microorganism is known, there are a number of problems associated with these processes. Most of them describe batch fermentation processes where the nutrients are added or mixed in with the microorganism in the culture medium at the beginning of the production process. Generally, (the fixed amount of) these nutrients are therefore gradually used up during fermentation. However, at the beginning of the process, because the nutrients are at relatively high concentrations, production of desired compound is low because the microorganisms use carbon and nitrogen sources to grow, rather than to produce the drug. In such a process, the rate of production of the desired product is largely uncontrollable. Overall production levels are low because in the batch processes nutrients are in effect supplied only once to the microorganism and so no variation (at least during production) can be conducted to balance growth of the biomass with production of the fermentation product.
Till date the best producers of spinosyns are different strains of Saccharopolyspora spinosa. However, Saccharopolyspora spinosa requires extensive fermentation duration for spinosyn formation in the culture broth and purification procedures (U.S. Pat. No. 5,362,634).
The present disclosure overcomes the limitations associated in the prior art mentioned above.